- Within 60 days prior to study entry, use of systemic azole antifungals (voriconazole, itraconazole, ketoconazole), dexamethasone, macrolide antibiotics (azithromycin, clarithromycin, erythromycin), antiretrovirals that are inhibitors of, or are metabolized by CYP3A4 (atazanavir, ritonavir, nelfinavir, indinavir, saquinavir, darunavir, lopinavir, rilpivirine, maraviroc), cobicistat, warfarin, nefazodone, rifamycins (rifabutin, rifampin, rifapentine), St. John's Wort, carbamazepine, phenytoin, phenobarbital, amiodarone, dofetilide, pimozide, procainamide, quinidine, sotalol, & birth control products containing estrogen, drugs that are p-glycoprotein inhibitors, & drugs that prolong the QTc interval with a risk of Torsades de Pointes